Since some of us are Windows developers, here's an interesting link: Microsoft's Design Principles for Windows (http://msdn.microsoft.com/en-us/library/aa511328.aspx). Very useful if you're designing new applications for Windows and want your app to look and feel like a standard Windows app.
Quite a read, there's lots there. I also found this very useful page: Windows standard keyboard shortcut keys (http://msdn.microsoft.com/en-us/library/bb545461.aspx)
I've noticed that MSDN has learnt a lot from Google. There's a lot less clutter in many newer areas.